Information systems may use some form of access control to determine what each of the system's users can do. Some access control systems are coarse-grained, employing a large-scale specification defining various permissions for users. In contrast, fine-grained access control systems, may undertake decisions with more detail and smaller scope. To provide fine-grained behavior, an access control system may grant (or deny) access for specific users or groups to specific items of interest in different contexts.